For $f(x)=2x+1$ And $g(x)=x^2-7$, Find $(f \cdot G)(x$\].A. $2x^3-x^2-7x-7$ B. $2x^3+x^2-14x-7$ C. $2x^2-13$ D. $3x^2+7x-6$

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Introduction

In algebra, multiplying two polynomial functions involves multiplying each term of one function by each term of the other function and then combining like terms. In this article, we will explore how to multiply two polynomial functions, using the given functions f(x)=2x+1f(x)=2x+1 and g(x)=x2โˆ’7g(x)=x^2-7 as examples.

Understanding Polynomial Functions

Before we dive into multiplying the functions, let's briefly review what polynomial functions are. A polynomial function is a function that can be written in the form anxn+anโˆ’1xnโˆ’1+โ€ฆ+a1x+a0a_nx^n + a_{n-1}x^{n-1} + \ldots + a_1x + a_0, where anโ‰ 0a_n \neq 0 and nn is a non-negative integer. The terms of a polynomial function are the individual terms that make up the function, such as 2x2x and 11 in the function f(x)=2x+1f(x)=2x+1.

Multiplying the Functions

To multiply the functions f(x)=2x+1f(x)=2x+1 and g(x)=x2โˆ’7g(x)=x^2-7, we need to multiply each term of one function by each term of the other function. This means that we will multiply each term of f(x)f(x) by each term of g(x)g(x) and then combine like terms.

Step 1: Multiply Each Term of f(x)f(x) by Each Term of g(x)g(x)

To multiply each term of f(x)f(x) by each term of g(x)g(x), we will use the distributive property of multiplication over addition. This means that we will multiply each term of f(x)f(x) by each term of g(x)g(x) and then combine like terms.

For example, to multiply the term 2x2x in f(x)f(x) by the term x2x^2 in g(x)g(x), we will multiply 2x2x by x2x^2 to get 2x32x^3. To multiply the term 2x2x in f(x)f(x) by the term โˆ’7-7 in g(x)g(x), we will multiply 2x2x by โˆ’7-7 to get โˆ’14x-14x.

Step 2: Combine Like Terms

After multiplying each term of f(x)f(x) by each term of g(x)g(x), we will combine like terms. This means that we will add or subtract terms that have the same variable and exponent.

For example, to combine the terms 2x32x^3 and โˆ’2x3-2x^3, we will add them together to get 4x34x^3. To combine the terms โˆ’14x-14x and 7x7x, we will subtract them to get โˆ’21x-21x.

Step 3: Write the Final Answer

After combining like terms, we will write the final answer. This means that we will write the resulting polynomial function in the form anxn+anโˆ’1xnโˆ’1+โ€ฆ+a1x+a0a_nx^n + a_{n-1}x^{n-1} + \ldots + a_1x + a_0.

For example, if we multiply the functions f(x)=2x+1f(x)=2x+1 and g(x)=x2โˆ’7g(x)=x^2-7, we will get the resulting polynomial function (fโ‹…g)(x)=2x3โˆ’14xโˆ’7(f \cdot g)(x) = 2x^3 - 14x - 7.

Conclusion

In conclusion, multiplying two polynomial functions involves multiplying each term of one function by each term of the other function and then combining like terms. By following the steps outlined in this article, we can multiply two polynomial functions and write the resulting polynomial function in the form anxn+anโˆ’1xnโˆ’1+โ€ฆ+a1x+a0a_nx^n + a_{n-1}x^{n-1} + \ldots + a_1x + a_0.

Example Solution

Let's use the functions f(x)=2x+1f(x)=2x+1 and g(x)=x2โˆ’7g(x)=x^2-7 as examples to illustrate how to multiply two polynomial functions.

Step 1: Multiply Each Term of f(x)f(x) by Each Term of g(x)g(x)

To multiply each term of f(x)f(x) by each term of g(x)g(x), we will use the distributive property of multiplication over addition.

f(x)โ‹…g(x)=(2x+1)โ‹…(x2โˆ’7)f(x) \cdot g(x) = (2x+1) \cdot (x^2-7)

=2xโ‹…x2โˆ’2xโ‹…7+1โ‹…x2โˆ’1โ‹…7= 2x \cdot x^2 - 2x \cdot 7 + 1 \cdot x^2 - 1 \cdot 7

=2x3โˆ’14x+x2โˆ’7= 2x^3 - 14x + x^2 - 7

Step 2: Combine Like Terms

After multiplying each term of f(x)f(x) by each term of g(x)g(x), we will combine like terms.

2x3โˆ’14x+x2โˆ’72x^3 - 14x + x^2 - 7

=2x3+x2โˆ’14xโˆ’7= 2x^3 + x^2 - 14x - 7

Step 3: Write the Final Answer

After combining like terms, we will write the final answer.

(fโ‹…g)(x)=2x3+x2โˆ’14xโˆ’7(f \cdot g)(x) = 2x^3 + x^2 - 14x - 7

Answer

Introduction

In our previous article, we explored how to multiply two polynomial functions using the given functions f(x)=2x+1f(x)=2x+1 and g(x)=x2โˆ’7g(x)=x^2-7 as examples. In this article, we will answer some common questions that students often have when multiplying two polynomial functions.

Q&A

Q: What is the difference between multiplying two polynomial functions and adding or subtracting two polynomial functions?

A: When multiplying two polynomial functions, we multiply each term of one function by each term of the other function and then combine like terms. When adding or subtracting two polynomial functions, we add or subtract the corresponding terms of the two functions.

Q: How do I know which terms to combine when multiplying two polynomial functions?

A: When multiplying two polynomial functions, we combine like terms by adding or subtracting the corresponding terms of the two functions. For example, if we have the terms 2x32x^3 and โˆ’2x3-2x^3, we will add them together to get 4x34x^3.

Q: Can I multiply two polynomial functions with different variables?

A: Yes, you can multiply two polynomial functions with different variables. For example, if we have the functions f(x)=2x+1f(x)=2x+1 and g(y)=y2โˆ’7g(y)=y^2-7, we can multiply them together to get (fโ‹…g)(x,y)=2xy2โˆ’14y+x2โˆ’7(f \cdot g)(x,y) = 2xy^2 - 14y + x^2 - 7.

Q: How do I know which terms to multiply when multiplying two polynomial functions?

A: When multiplying two polynomial functions, we multiply each term of one function by each term of the other function. For example, if we have the functions f(x)=2x+1f(x)=2x+1 and g(x)=x2โˆ’7g(x)=x^2-7, we will multiply each term of f(x)f(x) by each term of g(x)g(x) to get 2xโ‹…x2โˆ’2xโ‹…7+1โ‹…x2โˆ’1โ‹…72x \cdot x^2 - 2x \cdot 7 + 1 \cdot x^2 - 1 \cdot 7.

Q: Can I multiply two polynomial functions with different degrees?

A: Yes, you can multiply two polynomial functions with different degrees. For example, if we have the functions f(x)=2x+1f(x)=2x+1 and g(x)=x2โˆ’7g(x)=x^2-7, we can multiply them together to get (fโ‹…g)(x)=2x3โˆ’14x+x2โˆ’7(f \cdot g)(x) = 2x^3 - 14x + x^2 - 7.

Q: How do I know which terms to simplify when multiplying two polynomial functions?

A: When multiplying two polynomial functions, we simplify the resulting expression by combining like terms. For example, if we have the expression 2x3โˆ’14x+x2โˆ’72x^3 - 14x + x^2 - 7, we can simplify it by combining the like terms to get 2x3+x2โˆ’14xโˆ’72x^3 + x^2 - 14x - 7.

Conclusion

In conclusion, multiplying two polynomial functions involves multiplying each term of one function by each term of the other function and then combining like terms. By following the steps outlined in this article, we can multiply two polynomial functions and write the resulting polynomial function in the form anxn+anโˆ’1xnโˆ’1+โ€ฆ+a1x+a0a_nx^n + a_{n-1}x^{n-1} + \ldots + a_1x + a_0.

Example Solutions

Let's use the functions f(x)=2x+1f(x)=2x+1 and g(x)=x2โˆ’7g(x)=x^2-7 as examples to illustrate how to multiply two polynomial functions.

Example 1: Multiplying Two Polynomial Functions with Different Variables

f(x)โ‹…g(y)=(2x+1)โ‹…(y2โˆ’7)f(x) \cdot g(y) = (2x+1) \cdot (y^2-7)

=2xโ‹…y2โˆ’2xโ‹…7+1โ‹…y2โˆ’1โ‹…7= 2x \cdot y^2 - 2x \cdot 7 + 1 \cdot y^2 - 1 \cdot 7

=2xy2โˆ’14y+y2โˆ’7= 2xy^2 - 14y + y^2 - 7

Example 2: Multiplying Two Polynomial Functions with Different Degrees

f(x)โ‹…g(x)=(2x+1)โ‹…(x2โˆ’7)f(x) \cdot g(x) = (2x+1) \cdot (x^2-7)

=2xโ‹…x2โˆ’2xโ‹…7+1โ‹…x2โˆ’1โ‹…7= 2x \cdot x^2 - 2x \cdot 7 + 1 \cdot x^2 - 1 \cdot 7

=2x3โˆ’14x+x2โˆ’7= 2x^3 - 14x + x^2 - 7

Example 3: Simplifying the Resulting Expression

f(x)โ‹…g(x)=2x3โˆ’14x+x2โˆ’7f(x) \cdot g(x) = 2x^3 - 14x + x^2 - 7

=2x3+x2โˆ’14xโˆ’7= 2x^3 + x^2 - 14x - 7

Answer

The final answer is: 2x3+x2โˆ’14xโˆ’7\boxed{2x^3 + x^2 - 14x - 7}